£1800 is £1500 before VAT. Right now £1500 is US$2,330.25. The premium for buying in the UK is therefore only about 6%. It's not really worth applauding but these sort of stories usually seem to attract misinformation.
Is it worth getting the machine at all? The extra pixels are actually fantastically useful because if you don't want to run at a pretend 1440x900 you can jack up the desktop resolution to a pretend 1920x1200 and due to the pixel density everything still looks perfectly sharp*. So you can finally fit a desktop worth of stuff onto a laptop screen.
It'd be nice if other manufacturers would follow that sort of lead but I guess we're going to have to wait for Microsoft to ditch the desktop completely (as Boot Camp shows it to scale very poorly but Metro-as-was to scale flawlessly) or for Google to make a Chrome move before we get anything usable.
(*) internally that's implemented as rendering the desktop at 3840x2400 and sampling down so the scaler is throwing away information rather than trying to guess it — always a much better position to be in.